More than a tenth all of those fleeing war in Ukraine arrived in the Polish capital.
Some people want to stay in Warsaw or to settle there, while others use it as a point of transit to get further west. Warsaw's train stations have become crowded hubs, where people camp out on floors.
"We are facing the most severe migration crisis Europe has seen since World War II. ... The situation is becoming more and more difficult each day," Mayor Rafal Trazaskowski stated, adding that "the greatest challenges are still ahead of us."
As Ukraine struggles to resist Russia's invasion, Warsaw has shown its support and welcomed Ukrainians wholeheartedly. People have rallied to assist in the city. People are welcoming Ukrainians into their homes and collecting donations. They also volunteer at reception centers. In solidarity, city monuments and buses display the blue-and-yellow flag of Ukraine.
The challenge is immense. Volunteers who take time off from work are carrying a lot of the burden. This is not sustainable long-term.
Trzaskowski observed on Friday that one instance of a child psychologist volunteering to help refugees was a sign that they will soon need to return to work.
Also, housing is a problem. 95% of the Ukrainians who arrived in Warsaw during World War II were already residents and had been adopted by relatives or friends. The mayor stated Friday that 70% of new arrivals are from this group today, meaning 30% "need a roof above their heads" or other support.
As a result, the city is less able to handle large numbers of refugees.
Late Thursday, 15 children from Ukraine arrived at the Medyka border crossing to Poland. They were taken on a special medical train that took them to different hospitals throughout the country.
Dr. Dominik Daszuta is an anesthesiologist from Central Medical Hospital MSWIA in Warsaw. He described the way that the medical train was equipped with intensive care capabilities. As he spoke, medical staff helped children with strollers to board the train for Gdynia.
"In the beginning, people who arrived here fled in panic from the wars they had seen in the media or heard about. Dorota Zawadzka is a volunteer child psychologist at the Torwar sports centre's refugee center.
"This is a totally different type of refugee. They fear everything. They are content to wear their jackets. They are afraid, they don’t want to play, and their mothers have such empty eyes.
After initially trying to remain in Ukraine, Lena Nagirnyak (35-year-old Kyiv woman) found refuge at Torwar with her family. After hearing a low-flying bomber, they fled on foot from Bucha towards Irpin.
"The street where we were walking was bombed the next day." She said that if we had not left the next day, we could have died.
According to Friday's report by the International Organization for Migration, 2.5 million people have fled war-torn countries. More than half of them go to Poland. According to Poland's Border Guard agency, more than 1.5 million people had fled Poland as of Friday.
Trzaskowski stated that over 320,000 people had traveled through Warsaw during the conflict and that 230,000 people were still living in the city of over 1.7 million.
Others parts of the region also are under pressure. Even though the Czech Republic does not directly border Ukraine, it has around 200,000 refugees, most of them in Prague. The city hall began preparing temporary housing as the capital is running out of housing options.
Prague Mayor Zdenekhrib stated that the demand for accommodation in Prague was enormous and far exceeds what we have to offer.
The Czech government made an appeal to Czech citizens to shelter refugees in their homes and promised to find a way for them to be compensated.
Poland already took a similar step by approving a law that provided 40 zlotys ($9.20 per day) to refugees who were given shelter. It is part of a new legislative package, which also provides financial assistance and insurance for the Ukrainians.
The influx from Poland's west neighbor, Germany, has been concentrated in Berlin, the capital. Berlin is approximately an hour away from the Polish border, and the main destination for buses and trains from Poland.
Over 10,000 people arrive each day at the airport, according to authorities. Officials have been trying to spread the word about new arrivals to Germany, noting that they have greater chances of finding somewhere to live and can access medical care in Germany.
Friday's tweet by Germany's Interior Ministry in multiple languages stated that "rumors" that registration and arrival are only possible in Berlin were false and that anyone can register in Germany to receive assistance.